Packing for steam-pipes



(No Model.)

0. T. LEE.

I PACKING FOR STEAM PIPES. No. 411,384. Patented Sept. 17, 1889.

N, PETERS. Fholo-Lzlhfigrapher, Washmglon, D. C

UNITED STATES PATENT OFFICE.

CHARLES TENNANT LEE, OF BOSTON, MASSACHUSETTS, ASSIGNOR OF ONE- HALF TO THE GOULD & ATSON COMPANY, OF MASSACHUSETTS.

PACKING FOR STEAM-PIPES.

SPECIFICATION forming part of Letters Patent No. 411,384, dated September 1'7, 1889.

Application filed August 4, 1888- Serial No.28l ,93l. (N model.)

To aZZ whmn it may concern:

Be it known that I, CHARLES TENNANT LEE, of Boston, county of Sufi'olk, State of Massachusetts, have invented certain new and use- 5 ful Improvements in Packings or Insulators for Steam-Pipes, Electrical. Conductors, and the Like, of which the following is a specification, reference being had to the drawings accompanying and forming a part hereof, in

Which Figure 1 is a section showing a steam-pipe incased in my packing. Fig. 2 is a similar View showing the packing or insulator applied to electrical conductors.

The object of my invention is the production of a cheap and efficient packing or insulator which shall present great resistance to the passage of heat or electricity; and it consists in a layer or mass of comminuted mica in the form of flakes applied so as to surround the pipe or conductor and retained in place by a suitable case or boxing.

Mica is well known to be a good nonconductor, and it has been employ ed as such 2 5 when applied in sheets to parts of electrical apparatus. A packing or insulator should, to insure the greatest degree of n0n-conductivity, contain numerous air-spaces throughout its mass or body. For this reason, among others, hair-felt is a good ]10110O11Cl110l301, and is frequently used for packing steam-pipes, although it is not long-lived and requires to be frequently replaced.

Comminuted mica in flakes or scales of 3 5 varying sizes exists in large quantities where sheet-mica is cut or mined, and is at present of little or no value. I employ this flakemica, applying it as shown in the drawings, in

which a represents a steam-pipe, and Z) electrical conductors or wires. The mica (shown 4.0 at d) is placed around the pipe or conductors in a casingfiwhich may be of any desired shape and of any suitable material so long as it serves to retain the mica in place around the pipe or conductor. The mass of flakemica incloses an immense number of airspaces and forms an almost perfect non conductor for heat or electricity. Such an insulating material applied in this way has many obvious advantages besides its cheapness. Itispractically indestructible. \Vhen used around steam-pipes, if a leak occur it allows the water to drain off, and when dry is again in good condition. It is easily removed when repairs are necessary, and may be as easily replaced without the aid of special skill. Electrical wires may be threaded through a casing or conduit filled with it, as shown, Fig. 2, and thus easily pulled into place. It forms a close layer or mass around the conductor, and combines the porosity or numerous air-spaces of the felt packings with the great durability of mica, itself one of the best-known non-conductors.

lVhat I claim is A non-conductor for heat or electricity, consisting of comminuted mica in a loose state and unincorporated with other material, and retained in position around the pipe or conductor by a suitable box or casing, substan- 7o tially as shown and described.

CHARLES TENNANT LEE.

Vitnesses:

WM. A. MAOLEOD, ROBERT WALLACE. 

